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    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>

    <script>
        //迭代器
        // const arr = ['a', 'b', 'c']
        //     // for (let v of arr) {
        //     //     console.log(v);
        //     // }
        //     // console.log(arr);

        // let iterator = arr[Symbol.iterator]();
        // //调用对象的next方法
        // console.log(iterator.next());
        // console.log(iterator.next());
        // console.log(iterator.next());
        // console.log(iterator.next());

        //迭代器的应用
        //声明一个对象
        const banji = {
                name: '终极一班',
                stus: ['xiaoming', 'xiaoning', 'xiaotian', 'knight'],
                [Symbol.iterator]() {
                    //索引变量
                    let index = 0;
                    let _this = this
                    return {
                        next: function() {
                            if (index < _this.stus.length) {
                                const result = {
                                        value: _this.stus[index],
                                        done: false
                                    }
                                    //下标自增
                                index++;
                                return result
                            } else {
                                return {
                                    value: undefined,
                                    done: true
                                }
                            }
                        }
                    }
                }
            }
            //遍历这个对象
        for (let v of banji) {
            console.log(v);

        }
    </script>

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